1. Field of the Invention
The present invention relates to a reduction gear, a geared motor, and a product group thereof for use with industrial and transportation machinery and so forth.
2. Description of the Related Art
Conventionally it is known a reduction gear of an orthogonal or parallel shaft type for reducing power delivered from a motor or the like or for changing its rotational direction. In general, a motor is combined with the orthogonal shaft type reduction gear to change the rotational direction of power delivered from the motor, or with the parallel shaft type reduction gear to reduce only the speed thereof.
Alternatively, when the rotational direction needs to be changed and the speed needs to be reduced at the same time, a geared motor may be constructed in a combination of a motor and a reduction gear in which both the orthogonal transfer mechanism and the parallel shaft reduction mechanism are housed in one casing.
Although gear transfer mechanisms, friction transfer mechanisms or the like are available as reduction means for use with reduction gears, the gear transfer mechanism is employed mostly because the gear transfer mechanism can reduce the size of the resulting system and the cost thereof.
However, to construct a geared motor using prior art reduction gears, a separate (independent) reduction gear has been combined with a motor. Therefore, a variety of reduction gears to be prepared has required, for example, according to the size, type, use of the motor.
This has raised a stock cost of the reduction gear for reduction gear manufactures, and has raised a purchase price of the reduction gear for reduction gear users. The reduction gear users also needed to buy a new geared motor each time a slight change in use situation was made.
Furthermore, for gear arrangement convenience in the reduction gear, input and output shafts were restrictively positioned, resulting in a restricted position (or direction) for attachment of the reduction gear. Thus, the reduction gear could not be said to meet user needs (or user usability).